Electric-circuit breaker.



Patented July 22, |902.

No. 7o5,|o2.. H. w. LEONARD @L H. P. BALL.

ELECTRIC CIRCUIT BREAKER.

5 Sheets-Sheet (Application lad Apr. 4, 1898.)

(No Model.)

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No. 705,|02. Patented July 22, |902.

-H. W. LEONARD & H. P. BALL.

ELECTRIC CIRCUIT BREAKER.

v (Application filed Apr. 4, 1898.)

(lo Modal.) S'SheS-SheeiZ.

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THE Nonms PrsRs no. FHoYoUwo.. WASHINGTON, D. c.

No. `705,102. Patented .luly 22, |902.

H. W. LEONARD H. P. BALL.

ELECTRIC CIRCUIT BREAKER.

(Application filed Apr. 4, 1898.) (No Model.) 5 Sheetsf-Sheet 3.

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No. 705,!02. Patented .IuIy 22, |902.

H. W. LEONARD 8|. H. P. BALL.

ELECTRIC CIRCUIT BREAKER.

(Application filed Apr. 4, 1898,)

,5 Sheets-Sheet 4.

(No Model.)

- f I Ixptors @KQ Witnesses No. 705,|02. Patented July 22, |902.

H. W. LEONARD &. H. P. BALL.

ELECTRIC CIRCUIT BREAKER.

(Application led Apr. 4; 1898.)

5 Sheets-Sheet 5 l (No Model.)

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UNITED STATES HARRY WARD LEONARD, OF NEW PATENTy OFFICE.

YORK, AND HENRY PRICE BALL, OF

MOUNT VERNON, NEW YORK, ASSIGNORS, BY MESNE ASSIGNMENTS, TO H. WARDLEONARD, OF BRONXVILLE, NEV YORK.

ELECTRIC-CIRCUIT BREAKER.

SPECIFICATION forming part of Letters Patent N o. 705,102, dated July22, 1902.

Application filed April 4, 1898.

.To @Mw/wm it may concern:

Be it known that we, HARRY WARD LEON- ARD, a resident of the borough ofManhattan, city and county of New York, and HENRY PRICE BALL, a residentof Mount Vernon, in the county of Westchester,State of New York,citizens of the United States, have jointlyinvented a new and usefulImprovement in Automatic ElectrieOircuit Breakers, of which thefollowing is a description.

Our invention relates to circuit-breakers for automatically opening acircuit upon the occurrence of abnormal conditions in the circuit orupon the occurrence of a predetermined low of current.

The object of our invention is to provide better switch elements thanheretofore provided, to provide a better electroresponsive device forcontrolling the switch., and to provide means for insuring theinstantaneous operation of the switch when the electroresponsive deviceresponds to abnormal conditions.

In circuit-breakers as heretofore constructed the switch can be closedwhile an excessive current flows or while the line is shortcircuited,and the circuit-breaker will remain closed so long as the operator holdsthe operating-handle, thus subjecting the apparatus designed to becontrolled or protected thereby to the abnormal conditions of thecircuit, as well as subjecting the circuit breaker or controllingapparatus to destructive heating and arcing and frequently entirelydestroying the apparatus. Another objectionable feature incircuit-breakers as heretofore constructed is that the switch oftenfails to operate when the electromagnetic controller responds to anoverload current or cshort circuit. This is due to the sticking of theswitch-blades in the stationary switch-jaws and is true of switchesoperated both by grav ity and spring-pressure. Another objectionablefeature is the form of switchcontacts heretofore employed. lt iscustomary to provide one or more stationary switch members and a movablemember adapted to enter the stationary member, either the stationarymembers or the movable member being resilient, so that the movablemember will be Serial No. 676,411. (No model.)

wedged into the stationary member and produce a heavy frictionalengagement. Vith such constructions, however, perfect contact is notobtained throughout on account of the uneven spreading or compressing ofthe resilient member-that is to say, if, for instance, the stationarymember or members are resilient and the movable member a rigid blade theentrance of the blade will force the stationary members :farther apartat the entrance, thus causing them to assume a V shape, which results ina good contact at the lower or inner edge of the blade and agradually-decreasing degree of frictional engagement toward the outeredge and Very frequently producing an air-gap between a comparativelylarge area of the two switch elements. This condition producesoverheating atthe contacts. Various forms of wedgeshaped contacts andspringblades have been proposed to obviate' this difficulty; but, so sofar as we are aware, none of the constructions heretofore proposed haveovercome this objection.

7e have overcome the iirst objection by providing a double-polecircuit-breaker with entirely independent switch-arms, which aredesigned to be independently closed and independently or simultaneouslyopened automatically upon the occurrence of an overloadcurrent or shortcircuit. in such construction if one switch is closed while an excessivecurrent is iiowing the electromagnetic device will respond the instantthe second switch closes the circuit and effect the opening of theswitch Vfirst closed. Thus it will be seen that no mattei' how long theoperator may hold the second switch the first one will always operateinstantly to open the circuit if an overload exists.

The second objection is overcome by providing means for imparting a blowto the movable switch members when the electromagnetic controllerresponds to an overload current, the blow serving to start the movableswitch members from their stationary contact-jaws, whereupon the finalopening of the switch is effected either by spring-pressure or gravity,but preferably by springpressure. The devices for imparting blows IOO tothe movable switch members are preferably in the form of spring-actuatedoperating-handles, by means of which the switches are closed againstspring-pressure. Mech anical locking devices are preferably provided forlocking the switches in closed position. These devices preferably engagewith the operating-handles, so that upon the operation of theelectromagnetic controller the operating-handles are released and inmoving toward the open position impart the blows to the switches. Tofurther insure the opening of the switches, an additional spring issometimes provided for each switch, said springs exerting pressuredirectly upon the movable switch members while in the closed position,so that when the movable switch members receive a blow from theoperating-handles said springs aid the spring-actuated handles inopening the switches.

The third objection is overcome by our improved switch elements, whereinone eley ment, preferably the stationary member or members, is rigid andthe movable member is composed of two or more movable plates arrangedparallel to each other and having a spreading device between each plate.The object of the spreading device is to permit a free movement of theplates toward each other and also serves to produce good frictionalcontactbetween the plates and stationary switch member. The plates areloosely held by the movable switch-arm, and as they are forced betweenthe stationary switch members the spreaders are uniformly compressed,whereby the switch-plates remain parallel as they move into or betweenthe stationary members, thus producing a uniform and complete contact7there being no wedging action and no tendency to assume V-shapedpositions. However, if the adjacent faces of the stationary members werenot parallel the movable members would still make perfect contact,because the spreader will force them against the side walls, they beingloose and free to assume V-shaped positions, if necessary.

Our invention involves other details ot' construction, which will behereinafter more fully described.

In the accompanying drawings, which illustrate our invention, Figure lis a perspective view of a double-pole circuit-breaker embodying ourinvention, one switch being shown in the open position and the otherclosed. Fig. 2 is a side elevation showing one switch in the openposition, the other switch being omitted for the sake of clearness. Fig.3 is a side view showing the switch closed, the carbon contact beingremoved and parts being shown in section. Fig. 41 is a vertical centralsection of the electromagnetic controller. Fig. 5 is an elevation of theswitch-locking device; Fig. 6, an edge View of one of the movable switchmembers; Fig. 7, a View of the spring or spreader employed between theplates of the movable switch -blades 5 and Figs. 8 and 9 are diagramsillustrating the manner in which our improved circuitbreaker may beconnected in circuit, Fig. S showing the usual way of connecting aldouble-pole switch in circuit, while Fig. Q shows our preferredarrangement for connecting our double circuit-breaker in high-voltagecircuits, such as railway-circuitsthat is, the two switch members areconnected in series between the source of energy andthe controllingdevice.

rlhe electromagnetic controller comprises a solenoid-coil l, which islocated within an iron casing 2, the inner surface of which isinsulated, preferably, by a layer of mica 3. The ends of the coil areconnected to the terminals at, which are secured to the casing 2 andproperly insulated, and these terminals pass through the back of thesupport upon which the parts are mounted. Passing through the coil l isa brass tube 5 and also a layer of insulation U. lVithin the lower endof the brass tube is the core 7, which works through a hole in thebottom of the casing 2. At its lower end the core 7 is provided with adisk. of insulating material 8, held in place by a disk of metal 9.Projecting from the lower end of the core 7 is a rod l0, which passesthrough the screw-threaded sleeve 1l, which is screwed into a stirrup12, secured to the casing` 2. rlhe sleeve ,ll is adjustable through thestirrup to limit the lowermost or outward position of the core 7, and 13is a locking-nut for locking the sleeve ll in its adjusted position. Thelower end of rod l0 is provided with a knob 14: for operating the core 7by hand when it is desired to open the switches independently of thecurrent.

The `front of stirrup l2 is slotted, as shown in Figs. l and 4, andprovided with graduation-marks, indicating amperes. The edge ofthe metaldisk E) is beveled, so as to serve as a pointer, cooperating with thegraduations on the stirrup l2 and serving to indicate the number ofamperes at which the electromagnetic controller will operate. Vlfithinthe upper end of the tube 5 is a screw-threaded iron rod l5, whichscrews into the screw-threaded extension at the top of the casing 2 andwhich rod is provided with a tip l5, of non-magnetic material. Rod l5serves as an adjustable stop for the core 7. The object of this stop isto prevent injury to the locking device when the core operatesthat is,the disk S is designed to engage the locking device and trip it beforethe end of its movement-and the upward movement of the core is arrestedby the stop l5 before the locking device reaches the limit of itsmovement, so that the force of the blow will not injure the lockingdevice. 3y making the stop l5 large and of magnetic material it, withthe iron shell 2, greatly increases the magnetism of the solenoid.

Both switch members are identical in construction, and a description ofone of them will suffice for both. In the present form of IIO switch twostationary switch-contacts 16 are provided, having extensions 16, whichpass through the support or switchboard and by means of which and bolts17 the contacts are held in place. These contacts are rigid metal blockseach having one or more slots 1Gb, according to the number ofswitch-blades employed, the form shown in Fig. 1 having three slots andthe form shown in Figs. 2 and 3 having one slot. The movable switchmember is composed of a pivoted switch-arm 18, carrying one or moreswitch blades, each blade comprising a pair of comparatively thin plates18a, having a spreading device 181 between them. In the form shown inFig. 1 three blades are provided, the plates of each blade beingarranged in a pair of slots 18, formed in the switch-arm. The blades areheld in place by a bolt 18C, which passes through the plates and thespreading device and through one or more projections on the switch-arm.In Fig. 1 the projections through which bolt 18C passes are locatedbetween the blades, while in the form shown in Figs. 2, 3, and 6 twoprojections 18d are provided, the two plates 18a and spreader 18" beingplaced between them. From this construction it will be seen that eachpair of plates when forced into the slots of the stationary contactswill be held firmly against the sides thereof` by the spreading devicesbetween the plates, thus forming a perfect contact throughout. It willalso be seen that Ithe plates are free to adjust themselves in slots 16,even if they are slightly out of alinement, and if the walls forming theslots are not parallel the plates will also be free to adjustthemselves. It will also be seen that any desired degree of leXibilitymay be obtained by varying the thickness of the plates, since the propercurrent-carrying capacity of the blades can be obtained by providing anydesired number of plates, and as the number of plates is increased (withgood contact at each plate) the heating at the points of contact will bedecreased.

The movable switch-arm 18 is pivoted between two arms projecting from aspring-barrel 19a, secured to the switchboard by bolts 19", and thepivot end of the switch-arm is slotted to receive the operating-handle20,

' which is also pivoted between the two arms.

The operating-handle is provided with a flange or shoulder 20a, whichengages the switch-arm to move the same in closing the switch, and theend of the tongue 2Ob which passes through the slotted switch-arm isprovided with a flange or head 20, which constitutes the hammer forimparting a blow to the movable switch member to start it fromthestationary members. Theoperating-handle is provided with a slottedprojection carrying an antifriction-roller 20d, which engages aspring-actuated plunger 19, working in the barrel 19a, and as the switchis closed roller 20d engages with the upper end of the plunger 19,forcing said plunger downward and compressing its spring. It will beseen that as the operating-handle is released this plunger, actingagainst roller 20, will force the operating-handle outward and cause thehead 2Oc to impart a blow to the switch-arm and drive it outward or awayfrom the stationary contacts.

In closing the switch the switch blades or projections 18l engage with aspring-pressed plunger 2l and place its spring under increased tension.This plunger works in the barrel 21, projecting through the switchboard,as shown in Figs. 2 and 3. When the switch-blades are started from thestationary contacts by the blow of the operating-handle, plunger 21follows the blades and plunger 19 follows the operating-handle, theeffect of both being to greatly increase the momentum of the movableswitch member and producing a very rapid separation of the contacts, sorapid, in fact, that very little sparking is caused by the breaking ofthe circuit. It has been found in actual practice that the breakproduced by this switch is so rapid that the carbon contacts(hereinafter referred to) may be dispensed with without serious arcing.

The switch is locked by a catch 22, which engages a roller 2Oc on thetongue 201. This catch is secured to a spring-actuated arm 22, pivotedbetween two ears projecting` from an extension 16e of the lowerstationary contact member'. The spring serves to hold the catch in thelocking position. The arm is provided with a projection 22, which limitsthe forward movement of the catch, and said arm is of such length as toproject into the path of movement of the disk 8 on the core of theelectromagnetic controller, so that the upward movement of this diskwill tilt the catch and disengage it from the roller 20e on the tongueof the operating-handle.

To check the opening movement of the operating-handle afterthe openingof the switch is effected, we provide spring-plates 28 23 and a rubbercushion 23", the latter being seated in a shoulder 19c on thespring-barrel 19, and the former are secured to the sides of saidshoulder. Spring-plates 23 and 23L engage the operating-handle withconsiderable friction and in addition to checking the opening movementof the switch also prevent the operating-handle and the switch-arm fromrebounding.

To avoid injury to the metal switch-con tacts due to arcing upon theopening of the circuit, we provide a carbon break compris ing,preferably, carbon contacts 24E and 25, carried by curved spring-plates211i and 25, secured to the outer edges of the bases of the stationaryswitch members, and a carbon switch-plate 2G, secured to the outer sideof the movable switch-arm, so thatin the closed position plate 26 willbe between the pair of carbon contacts 24 and 25 and the switch-arm 18and in close contact with the contacts 2a and 25.

The preferred form of spreader :for the IOO IIO

switch-plates 18 is shown in detail in Fig. 7, in which 18b represents acrenelated springmetal plate (preferably phosphor-bronze) of the samesize as the switch-plates-that is, a plate cut alternately 'fromopposite edges to form a series of connected U -shaped sections, theconnected ends or sections 18e on one edge being bent out of alinementwith the corresponding ends or sections 18f on the opposite edge, asseen in Fig. 6, thus forming a springplate pressing' evenly along thelongitudinal edges of a pair of switch-plates when placed in position onthe switch-arm and always tending to hold said switch-plates parallel.The

switch-plates and spreader (which in the central section is left solid)are provided with central holes 18h for the bolt 18C. This bolt is theonly means for holding the plates of each switch -blade on theswitch-arm, the plates being held in alinement by being` placed inshallow slots 18h Fig. 1. From the foregoing and by reference to Fig. 1it will readily be seen that the switch-blades, by reason of theirflexibility and adjustability, will be capable of entering the slots ofthe stationary switch members even if they are not in alinement and thatthey will be free to adj ust themselves to the walls of the stationarycontacts whether they be parallel or not.

The open position of the switch is shown in Figs. 1 and 2. In thisposition the operatinghandle is held by the spring-clips 23 23a and themovable switch-arm 18 is resting upon the iiange 20a. To close theswitch, the operating-handle is disengaged from the springclips, whichmovement carries the switcharm upward and at the same time compressesthe spring of plunger 19. As the switchblades enter the stationarycontacts springplunger 21 is forced inward, compressing its spring, andwhen the switch blades have moved the proper distance into thestationary contacts 16 the latch 22 engages the roller 2Od and locks theswitch 'in the closed position, as shown in Fig. 3.

Under normal conditions the core of the electromagnetic controller willrest in its lowermost position against the screw-.sleeve 11, and, asabove stated, upon the occurrence of an overload-current of thepredetermined amount for which the controller is adjusted the core 7will be drawn upward, causing the disk 8 to strike the end of arm .22iLof the locking device, tripping the same and effecting the release ofthe switch-operating handle, whereupon spring-plunger 19 will throw thehandle outward, which in its movement will impart a blow to theswitch-arm, starting the switch-blades from the stationary contacts, andthen the combined pressure of spring-plungers 19 and 21 will effect thenal opening movement of the switch. It may be noted that the lockingdevice is also tripped by a blow instead of a steady pull, which makesthe release more e'ective. A steady pull on the locking device might beineffective to release the catch, while a sharp blow will insure apositive and instantaneous release. It will also be noted that while wehave described the elements of our circuitbreaker as applied to theoverload typethat is, one operating when the current eX- ceeds apredetermined amount or when a short circuit occursit is to beunderstood that our switch elements are equally as well adapted for usewith an underload electroresponsive device-that is, one operating whenthe current fails or falls below a predetermined amount.

The manner in which our circuit-breaker may be electrically connected incircuit is shown in Figs. 8 and 9, in which 35 represents a dynamo orother source of electric energy, and 36 is the translating device to beprotected by the automatic circuit-breaker. In Fig. 8 the connectionsrepresent the ordid nary double-pole switch connections-4l e., oneswitch in each side of the circuit. When the circuit-breaker is to beused on high* voltage circuits, such as railway-circuits, we connect thetwo switches in series between the source and the translating device-i.e., both switches in the salne side of the circuitthus providing fourpoints at which the circuit is broken simultaneously in one side of thecircuit, as shown in Fig. 9. With this arrangement the switch membersare not subjected to severe arcing, as in the ordinary arrangement, andby employing our form of independently-operating switches we retain theimportant advantage of our improved switch mechanism-4'. e., certainopening ot the cir cuit at the irst switch closed immediately upon theclosure ol' the second switch should abnormal conditions exist on theline at the instant the circuit is completed through both switches. Thusall the advantages of a multiple-contact switch are embodied in ourimproved switch and automatic circuit-breaker.

-What we claim is- 1. The combination of a plurality of electricswitches designed to be moved manually and independently into normalposition, and a single controlling device for automatically controllingthe movement of said switches after manual adjustment.

2. The combination ot a plurality ot' electric switches designed to bemoved manually and independently into normal position, and a singleelectroresponsive device for automatically controlling the movement ofsaid switches after manual adjustment.

3. The combination of a plurality of electric switches designed to bemoved manually and independently into normal position, and a singleelectroresponsive device for automatically controlling or effecting thesimultaneous movement of said switches after manual adjustment.

4. The combination of a plurality of electric switches designed to bemoved manually and independently into normal position, means tending toopen said switches, locking devices for holding said switches in theirIOO IIO

normal positions, and a single electroresponsive device forautomatically releasing said switches.

5. The combination of a plurality of electric switches designed to bemoved manually and independently into normal position, means tending toopen said switches, locking devices for holding said switches in theirnormal positions, and a single electroresponsive device forautomatically and simultaneously releasing said switches.

6. The combination ot' a plurality of electric switches, means tendingto move same out of normal position, a locking device for holding eachof said switches in normal position, an automatic controller foreffecting the release of said switches, and means operating to impart ablow to said switches to start same when released.

7. The combination of a plurality of electric switches, means tending tomove same independently out of normal position, a locking device forholding each of said switches in normal position, an automaticcontroller for eifecting the release of said switches independently orsimultaneously, and means operating toimpart a blow to said switches tostart same when released.

8. The combination of a plurality of electric switches, means tending tomove same out of normal position, a locking device for holding each ofsaid switches in normal position, an electroresponsive device foreffecting the release ot' said switches, and means operating to impart ablow to said switches to start same when released.

9. The combination of a plurality oi electric switches, means tending tomove same independently out of normal position, a locking device forholding each or" said switches in normal position, an electroresponsivedevice for effecting the release of said switches independently orsimultaneously, and means operating to impart a blow to said switches tostart same when released.

10. In a circuitcontroller, the combination of a plurality of switchesadapted to be connected in series in one side of an electrical circuit,means for operating said switches, and one electroresponsive device forcontrolling the operation of said switches.

11. In a circuit-controller, the combination of a plurality of switchesadapted to be connected in series in one side of an electrical circuit,means for operating said switches, and one electroresponsive device forsimultaneously controlling the operation of said switches.

12. In a circuit-controller, the combination of a plurality of switchesadapted to be connected in series in one side of an electrical circuit,means for operating said switches, independent means for holding eachswitch closed under normal conditions, aud one electroresponsive deviceoperating under abnormal conditions to effect the release of saidswitches.

13. In a circuit-controller, theI combination of a plurality of switchesadapted to be connected in series in one side of an electrical circuit,means for operating said switches independently, and means common toeach of said switches operating under abnormal conditions in the circuitto cause one or all of said switches when closed to open automaticallyupon the completion of the circuit.

14. ln a circuit-controller, the combination of a plurality of switchesadapted to be connected in series in one side of an electrical circuit,means for operating said switches independently, independent means 'lormaintaining each switch closed under normal conditions, and anelectroresponsive device operating under abnormal conditions in thecircuit to cause the release of one or all of said switches when closedto open automatically upon the completion of the circuit.

15. In an automatic circuitebrealier, the combination of two independentswitches electrically connected in series, and a single means openingboth switches when the current in the circuit exceeds a predeterminedmaximum.

16. An electric-circuit breaker having in combination an armcarryingloosely-mounted contact-blades, a stationary slotted contacthaving rigid walls between which said blades are adapted to enter, saidarm being actuated to fly forward through spring-pressure, a latch forholding said arm in the normal position, and means for releasing saidlatch.

17. An electric-circuit breaker having in combination an arm carryinglooselymounted contact-blades, a stationary slotted contact having rigidwalls between which said blades are adapted to enter, said arm beingactuated to ily forward through spring-pressure, a latch for holdingsaid arm in the normal position, and an electroresponsive deviceoperating under abnormal conditions to disengage said latch.

18. An electric-circuit breaker having in combination an arm carryingloosely-mounted contact-blades, a stationary slotted contact havingrigid walls between which said blades are adapted to enter, said armbeing actuated to iiy forward through spring-pressure, a latch forholding said arm in the nor mal position, a device for imparting a blowto said arm when the latch is disengaged, and an electroresponsivedevice operating under abnormal conditions to disengage said latch.

19. In an electric switch, the combination of a stationary slottedcontact member, and a movable member having one or more blades adaptedto enter said slots, each blade comprising a plurality ofloosely-mounted contact-plates with spreading devices between them.

20. ln an electric switch, the combination ICO IIO

ble contact-plates with spreading devices between them.

2l. In an electric switch, the combination ot a stationary slottedcontact member', and a movable member having one or more blades adaptedto enter said slots, each blade comprising a pair of loosely-mountedcontactplates with a spreading device between each pair of plates.

22. In an electric switch, the combination of a stationary slottedcontact member, and a movable member having onel or more blades adaptedto enter said slots, each blade comprisingr a pairof looselymountedflexible contact-plates with a spreading device between each pair ofplates.

23. In an electric-circuit breaker such as described, the contact-makingparts consist ing of loosely-mounted blades with spreading devicesbetween them, and slotted metal blocks for the blades to enter, incombination with an electroresponsive means to open said contacts.

24. The combination of arms having contactblades loosely mountedthereon, the blades being arranged in pairs with spreading devicesbetween them, slotted blocks or parts for the blades to enter, twoblades in each slot, and automatic means for withdrawing the blades fromthe slots simultaneously, as described.

25. The combination of pivoted arms having contact-blades looselymounted thereon, the blades being arranged in pairs with spreadingdevices between them, slotted blocks or parts for the blades to enter,two blades in each slot, and electroresponsive means controlling thewithdrawal of the blades from the slots simultaneously, as described.

2G. The combination of pivoted arms having contact-blades looselymounted thereon, the blades being arranged in pairs with spreading`devices between them, slotted blocks or parts for the blades to enter,two blades in each slot,and electromagnetic means controlling thewithdrawal of the blades from the slots simultaneously, as described.

27. A circuit-breakerof the character hercin described, consisting ofthree independent parts, namely, two independently-operated switches orswitch members, and an electroresponsive device forcontrollingsaidswitches simultaneously or independently of each other.

28. A circuit-brealer of the character herein described, consisting ofthreeindependent parts, namely, two independently-operated switches orswitch members adaptedto be connected in series between a source ofenergy and a translating device, and an electroresponsive device forcontrolling said switches simultaneously or independently of each other.

29. In an automatic circuit-breaker, the combination of one or morestationary contact members, a movable spring-actuated switch member, aspring-actuated operatinghandle for closing the switch, a locking deviceior holding the operating-handle in the closed position of the switch,an electroresponsive device for controlling said locking device torelease the operating-handle, and means on said operating-handle wherebyupon its release a blow will be imparted to the switch to facilitate theopening movement of the switch.

30. In an automatic circuit-breaker, the combination with the stationaryand movable contact members, of a pivoted and independently-movableoperating-handle for moving the movable switch member to its closedposition, a spring placed under tension by the closing movement of theoperating-handle and tending to drive the operating-handle to itsinitial position, a catch for holding said operatingehandle against thepressure of said spring, electroresponsive means for automaticallyreleasing said operating-handle, and means on said operating-handlewhereby when the handle is released the movement imparted to it by thespring will iirst impart a blow to the movable switch member and theneilect the opening of the switch.

31. In an automatic circuit-breaker, the combination with the stationaryand movable contact members, of apivoted and independently-movableoperating-handle for moving the movable switch member to its closedposition, a spring placed under tension by the closing` movement of theoperatingdiandle and tending to drive the operating-handle to itsinitial position, a catch for holding said operating-handle against thepressure of said spring, a second spring placed under tension by theclosing movement of the movable switch member and tending to drive saidmember away from the stationary contacts, electroresponsive means forautomatically releasing said operating-handle, and means on saidoperating-handle whereby when the handle is released the movementimparted to it by its spring will first impart a blow to the movableswitch and the combined action of both springs will effect the nalopening of the switch.

32. A multipolar circuit-breaker, comprising a number of switches, eachof which is capable of independent operation to open or close a circuit,and automatic means for open ing all of the switches.

33. In a multipolar circuit-breaker, the combination of a number ofswitches, each of which is capable of independent operation to open orclose a circuit, with a common tripping device acting to open all of thecircuits, and a coil controlling the action of the trip.

534-. In a circuit-breaker, the combination of a number of switches indifferent leads or wires, each capable of independent operation, with anoverload or series coil, an armature, and a device actuated by thearmature for simultaneously releasing all of the switches to open theircircuit, leavingr them free to IOO IIO

close the circuit successively or simultaneously, as may be desired.

35. In a double-pole circuit-breaker, the combination ot' two switcheshaving no mechanical connection, one in each side of the circuit,automatic means for simultaneously opening` the switches at desiredtimes, and means permitting their closure successively orsimultaneously.

36. The combination of two independentlyoperated switches in the twosides of a circuit, a tripping device for each switch, an armature forsimultaneously actuating both tripping devices, and aseries coil in oneside only of the line.

37. The combination, with an electric circuit, of two circuit-breakersresponsive to the same load connected with opposite sides of the circuitand located adjacent to one another, and magnetic means responsive to apredetermined variation of current strength, for opening the circuit atone circuit-breaker if a current variation exists when the other isclosed.

38. In an automatic circuit-breaker, two

ci1'cuit-inte1''1upting devices in series relation, provided withindependent means of operation and adapted for inclusion in an electriccircuit so as to be under the control of the same operator, eachcircuit-interrupting device being automatically responsive to the samepredetermined increase of current strength, whereby the circuit will beopened at one point if an overload exists when it is closed at the otherpoint.

39. The combination with an electric circuit, of two automatic magneticcircuit-breakers connected in series relation, provided with independentclosing means and placed in proximity to one another, eachcircuit-intern rupting device being responsive to a determinatevariation of current strength, whereby the circuit will be opened at theswitch of the circuit-breaker if a determinate strength of currentexists when the other is closed.

H. WARD LEONARD. HENRY PRICE BALL. lVitnesses:

R. H. MANSFIELD, J r., C. E. CARPENTER.

